In recent years, disposition of objects having various functions on an inner surface of a pneumatic tire and methods for the disposition have been variously examined.
An attaching method, for example, has been proposed in which tire tags (radio frequency identification tags), chips, or the like are attached to an inner liner or the like of a green tire using a so-called surface fastener such as a hook-and-loop fastener or a hook-and-hook fastener (Patent Document 1).
Additionally, a pneumatic tire has been proposed in which a surface fastener is vulcanization bonded to a region corresponding to a tread of a tire inner surface, and a noise absorbing material is attached to the tire inner surface via the surface fastener (Patent Document 2).
The attaching methods using the surface fasteners proposed in these Patent Document 1 and Patent Document 2 are preferable in that relatively strong engagement force is achieved when attached. The methods are also preferable in that engagement on a surface can be achieved without slight misalignments when attaching becoming a problem.
However, with the attaching methods using surface fasteners proposed in the patent documents, a state in which the individual engaging elements of the surface fastener are engaged is not ideal due to such as the curved inner circumferential surface of the pneumatic tire being an annular, curved surface, thus the edge portions, mid-portion, or similar portion may become partially raised. Accordingly, an amount of the obtained engagement force may vary (positional variation within the tire and variation from tire to tire). As a result, in some cases, the expected engagement force was not able to be obtained. In these methods, repetitive deformation and compression are performed over an extended period of time caused by rolling at high speeds in a state of relatively elevated temperatures. This may cause partial physical deterioration and deterioration/degradation over time of the engagement force of an entirety of the surface fastener accompanying the progression of the partial physical deterioration. This may lead to cases in which difficulties have been met in maintaining a desired engagement force over an extended period of time.
To solve the problems, the inventors of the present invention have previously proposed a pneumatic tire that includes one fastener among a pair of mechanical fasteners that can be separated into two at a tire inner surface (Japanese Laid-Open Patent Publication No. 2010-167839). In the method for attaching an object employed for the pneumatic tire, the obtained engagement force is especially large, and an amount of the obtained engagement force hardly varies (positional variation within the tire and variation from tire to tire). Additionally, in the attaching method, deterioration and degradation over time of the engagement force is less likely to occur even under as sever usage condition of repetitive deformation and compression over an extended period of time caused by fire rolling at high speeds in a state of relatively elevated temperatures. This allows maintaining a desired engagement force over long period.
Here, a mechanical fastener means a fastener configured with a pair of fasteners. The pair of fasteners can be separated into two fasteners. The pair of fasteners can be physically re-engaged. This engaging and separating can be freely repeated.
A typical mechanical fastener is those called as hooks or snaps. The mechanical fastener is generic term for products in, for example, the clothing industry. More specifically, the mechanical fasteners generally include snap buttons, ring snaps, ring hooks. American snaps, American hooks, eyelet hooks, spring books, jumper hooks, and similar hooks. Such mechanical fasteners differ from so-called “surface fastener” in that while an area of the engaging part of a surface fastener is unlimited in the entire area. So to speak, mechanical fasteners are point fasteners with small-area engaging part (e.g. preferably from about 1 to 115 mm2 and more preferably from about 4 to 90 mm2). In other words, even when engaged at a small area of, for example, from about 1 to 115 mm2, due to a mechanical male-female structure or the like, the mechanical fasteners achieve strong engaging. Thus, a conventional structure for the mechanical fastener may be used. The mechanical fastener can be formed from materials such as metals, rubbers, synthetic resins, and the like. The method using the mechanical fastener is excellent in, for example, an amount of obtained engagement force, variation of the amount of obtained engagement force, and certainty of the engagement operation.
One fastener among the mechanical fasteners mounted on the tire inner circumferential surface is shown in FIG. 5. In FIG. 5, the tire inner surface 2 of a pneumatic tire 1 includes a one fastener 3 (3A) among a pair of mechanical fasteners that can be separated into two fasteners. Reference numeral 4 denotes a tread, reference numeral 5 denotes a sidewall, and reference numeral 6 denotes a bead. The mechanical fastener 3 includes a pair of fasteners. The pair of fasteners includes the depressed-shaped or the female-shaped fastener 3A as shown in FIG. 6A and the convex-shaped or a male-shaped fastener 3B as shown in FIG. 6B. Engaged states of the fasteners are shown in FIG. 6C.
In the tire with a structure where the one fastener (3A) among the pair of mechanical fasteners is included at the tire inner surface, any given object with another fastener (3B) is engaged with the paired fastener (3A) on the tire inner surface side. Accordingly, the any given object is disposed at the inner surface of the pneumatic tire.
However, the disposition method or a disposition method using the above-described surface fastener has the following problem. That is the electronic circuit device such as an air pressure sensor may be mounted on the pneumatic tire by these methods. In this case, injection of liquid such as puncture repair liquid in the tire at puncture may cause the liquid to adhere to the electronic circuit device such as the air pressure sensor, thus damaging the electronic circuit device.